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The phosphoinositide 3-kinase (PI3K) pathway playing an important role in cell proliferation, growth, and survival is one of the most frequently dysregulated pathways in cancer. However, PI3K inhibitors, used as a monotherapy, have shown limited therapeutic efficacies and high rates of side effects from acquired resistance to PI3K inhibition via feedback loop-mediated pathway reactivation and poor tolerability of small-molecule inhibitors. Here, we proposed a multi-targeting siRNA delivery system using polymerized siRNA-based nanoparticle formulations (Msi-NPs) as a PI3K-targeted anticancer therapy for simultaneous ablation of Rac1 and p110β-subunit of PI3K linked by a Rac-PI3K positive feedback loop. Msi-NPs could self-assemble from polymerized siRNAs targeting Rac1 and p110β together with thiolated glycol chitosan. The combinatory inhibition of Rac1 and p110β successfully inhibited the PI3K signaling pathway in PI3K tumor suppressor phosphatase and tensin homolog (PTEN) deficient prostate cancer cells, resulting in significant delays in cell proliferation and migration. The Msi-NP delivery system can provide an alternative therapeutic strategy to overcome the challenges in PI3K inhibitor monotherapy.

Simple Summary Although various malignant tumors express high levels of lysyl oxidase (LOX) and though its role in tumor progression is well-defined, there is a lack of sensing techniques to target LOX. This study highlights the application of peptide-functionalized gold nanoprobes for sensing the LOX levels in tumor microenvironments. The gold nanoparticles (AuNPs) in these nanoprobes aggregate upon exposure to LOX, resulting in a red shift of the surface plasmon resonance peak, accompanied by a characteristic color change. This colorimetric assay based on peptide-functionalized AuNP sensitively detects LOX secreted from various cancer cells not only in vitro but also in the tissue extract. In this study, the suggested analytical approach demonstrated high specificity to LOX and did not show any color change in the presence of other enzymes. Abstract High LOX levels in the tumor microenvironment causes the cross-linking of extracellular matrix components and increases the stiffness of tumor tissue. Thus, LOX plays an important role in tumorigenesis and in lowering the tumor response to anticancer drugs. Despite comprehensive efforts to identify the roles of LOX in the tumor microenvironment, sensitive and accurate detection methods have not yet been established. Here, we suggest the use of gold nanoparticles functionalized with LOX-sensitive peptides (LS-AuNPs) that aggregate upon exposure to LOX, resulting in a visual color change. LOX-sensitive peptides (LS-peptides) contain lysine residues that are converted to allysine in the presence of LOX, which is highly reactive and binds to adjacent allysine, resulting in the aggregation of the AuNPs. We demonstrated that the synthesized LS-AuNPs are capable of detecting LOX sensitively, specifically both in vitro and in the tissue extract. Moreover, the suggested LS-AuNP-based assay is more sensitive than commonly employed assays or commercially available kits. Therefore, the LS-AuNPs developed in this study can be used to detect LOX levels and can be further used to predict the stiffness or the anticancer drug resistance of the tumor.

The phosphoinositide 3-kinase (PI3K) and RAS signaling pathways are frequently co-activated and altered during oncogenesis. Owing to their regulatory cross-talk, the early attempts of targeting only one pathway have mostly ended up promoting the development of drug resistance. Here, we propose using small interfering RNA (siRNA) therapeutics to directly target the undruggable KRAS (siKRAS) in combination with the pan-PI3K inhibitor GDC-0941 (GDC) to simultaneously block both PI3K and RAS signaling, thereby exerting synergistic anti-tumor effects on ovarian cancers with PTEN deficiency and KRAS(G12D) mutation. For successful delivery of siKRAS, tGC/psi—nanoparticle formulation of polymerized siRNA and thiol-modified glycol chitosan nanoparticle—was used for KRAS specific inhibition in vitro and in vivo. GDC or siKRAS monotherapy each impede downstream signaling, leading to some delay in cell proliferation and migration. When combined, however, they engender much higher inhibition of PI3K signaling and stimulation of apoptosis in an ovarian allograft model compared to monotherapies. Our results show the feasibility of developing new combination strategies for the management of multiple oncogenic mutations activating PI3K and RAS signaling.

Cancer immunotherapy is an attractive treatment option under clinical settings. However, the major challenges of immunotherapy include limited patient response, limited tumor specificity, immune-related adverse events, and immunosuppressive tumor microenvironment. Therefore, nanoparticle (NP)-based drug delivery has been used to not only increase the efficacy of immunotherapeutic agents, but it also significantly reduces the toxicity. In particular, NP-based drug delivery systems alter the pharmacokinetic (PK) profile of encapsulated or conjugated immunotherapeutic agents to targeted cancer cells or immune cells and facilitate the delivery of multiple therapeutic combinations to targeted cells using single NPs. Recently, advanced NP-based drug delivery systems were effectively utilized in cancer immunotherapy to reduce the toxic side effects and immune-related adverse events. Repurposing these NPs as delivery systems of immunotherapeutic agents may overcome the limitations of current cancer immunotherapy. In this review, we focus on recent advances in NP-based immunotherapeutic delivery systems, such as immunogenic cell death (ICD)-inducing drugs, cytokines and adjuvants for promising cancer immunotherapy. Finally, we discuss the challenges facing current NP-based drug delivery systems that need to be addressed for successful clinical application.

The use of nanomedicine for cancer treatment takes advantage of its preferential accumulation in tumors owing to the enhanced permeability and retention (EPR) effect. The development of cancer nanomedicine has promised highly effective treatment options unprecedented by standard therapeutics. However, the therapeutic efficacy of passively targeted nanomedicine is not always satisfactory because it is largely influenced by the heterogeneity of the intensity of the EPR effect exhibited within a tumor, at different stages of a tumor, and among individual tumors. In addition, limited data on EPR effectiveness in human hinders further clinical translation of nanomedicine. This unsatisfactory therapeutic outcome in mice and humans necessitates novel approaches to improve the EPR effect. This review focuses on current attempts at overcoming the limitations of traditional EPR-dependent nanomedicine by incorporating supplementary strategies, such as additional molecular targeting, physical alteration, or physiological remodeling of the tumor microenvironment. This review will provide valuable insight to researchers who seek to overcome the limitations of relying on the EPR effect alone in cancer nanomedicine and go "beyond the EPR effect".

Pancreatic cancer is one of the most lethal forms of cancer, predicted to be the second leading cause of cancer-associated death by 2025. Despite intensive research for effective treatment strategies and novel anticancer drugs over the past decade, the overall patient survival rate remains low. RNA interference (RNAi) is capable of interfering with expression of specific genes and has emerged as a promising approach for pancreatic cancer because genetic aberrations and dysregulated signaling are the drivers for tumor formation and the stromal barrier to conventional therapy. Despite its therapeutic potential, RNA-based drugs have remaining hurdles such as poor tumor delivery and susceptibility to serum degradation, which could be overcome with the incorporation of nanocarriers for clinical applications. Here we summarize the use of small interfering RNA (siRNA) and microRNA (miRNA) in pancreatic cancer therapy in preclinical reports with approaches for targeting either the tumor or tumor microenvironment (TME) using various types of nanocarriers. In these studies, inhibition of oncogene expression and induction of a tumor suppressive response in cancer cells and surrounding immune cells in TME exhibited a strong anticancer effect in pancreatic cancer models. The review discusses the remaining challenges and prospective strategies suggesting the potential of RNAi-based therapeutics for pancreatic cancer.

One of the most promising approaches for the treatment of colorectal cancer is targeting epidermal growth factor receptor (EGFR). Comprehensive research has led to significant clinical outcomes using EGFR-targeted anticancer drugs; however, the response to these drugs still largely varies among individuals. The current diagnostic platform provides limited information that does not enable successful prediction of the anticancer performance of EGFR-targeted drugs. Here, we developed a EGFR-targeted activatable probe for predicting therapeutic efficacy of EGFR-targeted doxorubicin prodrug in colorectal cancer therapy. The EGF-conjugated fluorescence-activatable probe (EGF-probe) and EGF-conjugated doxorubicin prodrug (EGF-prodrug) were both fabricated using peptide substrates that can be dissociated by lysosomal enzymes, and thus share an intracellular mechanism of action. We demonstrated that after EGFR-mediated endocytosis, lysosomal enzymes de-quench the fluorescence of EGF-probe and activate the cytotoxicity of EGF-prodrug. When evaluated in vivo, EGF-probe yielded an outstanding cancer-specific imaging ability with reduced background signals. EGF-prodrug also successfully targeted the tumor and promoted cancer cell death. We tested different colorectal cancer cell types to investigate the correlation between the fluorescence recovery efficiency of EGF-probe and the cytotoxicity of EGF-prodrug. Strong correlations were observed both in vitro and in vivo. The actions of EGF-probe and EGF-prodrug were dependent on the inherent lysosomal activity of the cell type rather than its EGFR expression level. Our proposed approach using EGF-probe and EGF-prodrug may overcome the major drawback of the conventional theranostic platform and provide great opportunity for successful personalized cancer therapy.

Nanomedicine is extensively employed for cancer treatment owing to its unique advantages over conventional drugs and imaging agents. This increased attention to nanomedicine, however, has not fully translated into clinical utilization and patient benefits due to issues associated with reticuloendothelial system clearance, tumor heterogeneity, and complexity of the tumor microenvironment. To address these challenges, efforts are being made to modify the design of nanomedicines, including optimization of their physiochemical properties, active targeting, and response to stimuli, but these studies are often performed independently. Combining favorable nanomedicine designs from individual studies may improve therapeutic outcomes, but, this is difficult to achieve as the effects of different designs are interconnected and often conflicting. Glycol chitosan nanoparticles (CNPs) are shown to accumulate in tumors, suggesting that this type of nanoparticle may constitute a good basis for the additional modification of nanoparticles. Here, multifunctional glycol CNPs designed to overcome multiple obstacles to their use are described and key factors influencing in vivo targeted delivery, targeting strategies, and interesting stimulus-responsive designs for improving cancer nanomedicine are discussed.

Rosacea is a chronic inflammatory skin disease characterized by immune response–dependent erythema and pustules. Although the precise etiology of rosacea remains elusive, its pathogenesis is reportedly associated with an increased level of antimicrobial peptide LL-37. However, molecular mechanisms underlying the progression of rosacea via LL-37 remain poorly understood. Here, we examined the potential role of LL-37 in rosacea-like skin inflammatory phenotypes at a molecular level. Our in vitro data demonstrated that LL-37 promotes NLRP3-mediated inflammasome activation in lipopolysaccharide-primed macrophages, indicated by the processing of caspase-1 and IL-1β. LL-37 was internalized into the cytoplasm of macrophages through P2X7 receptor–mediated endocytosis. Intracellular LL-37 triggered the assembly and activation of NLRP3-ASC inflammasome complex by facilitating lysosomal destabilization. Consistent with these in vitro results, intradermal LL-37 administration induced in vivo caspase-1 activation and ASC speck formation in the skin of Nlrp3-expressing, but not in Nlrp3-deficient, mice. Intradermal injection of LL-37 elicited profound recruitment of inflammatory Gr1+ cells and subsequent skin inflammation. However, LL-37–induced rosacea-like skin inflammation was significantly abrogated in Nlrp3-deficient mice. Furthermore, an NLRP3-specific inhibitor, MCC950, markedly reduced LL-37–triggered rosacea-like phenotypes. Taken together, our findings clearly indicate that NLRP3 inflammasome activation plays a crucial role in LL-37–induced skin inflammation and rosacea pathogenesis.

Thrombosis is an important pathophysiologic phenomenon in various cardiovascular diseases, which can lead to oxygen deprivation and infarction of tissues by generation of a thrombus. Thus, direct thrombus imaging can provide beneficial in diagnosis and therapy of thrombosis. Herein, we developed thrombin-activatable fluorescent peptide (TAP) incorporated silica-coated gold nanoparticles (TAP-SiO2@AuNPs) for direct imaging of thrombus by dual near-infrared fluorescence (NIRF) and micro-computed tomography (micro-CT) imaging, wherein TAP molecules were used as targeted thrombin-activatable peptide probes for thrombin-specific NIRF imaging. The freshly prepared TAP-SiO2@AuNPs had an average diameter of 39.8 ± 2.55 nm and they showed the quenched NIRF signal in aqueous condition, due to the excellent quenching effect of TAP molecules on the silica-gold nanoparticle surface. However, 30.31-fold higher NIRF intensity was rapidly recovered in the presence of thrombin in vitro, due to the thrombin-specific cleavage of quenched TAP molecules on the gold particle surface. Furthermore, TAP-SiO2@AuNPs were successfully accumulated in thrombus by their particle size-dependent capturing property, and they presented a potential X-ray absorption property in a dose-dependent manner. Finally, thrombotic lesion was clearly distinguished from peripheral tissues by dual NIRF/micro-CT imaging after intravenous injection of TAP-SiO2@AuNPs in the in situ thrombotic mouse model, simultaneously. This study showed that thrombin-activatable fluorescent peptide incorporated silica-coated gold nanoparticles can be potentially used as a dual imaging probe for direct thrombus imaging and therapy in clinical applications.

Background and Purpose— Quantitative imaging for the noninvasive assessment of thrombolysis is needed to advance basic and clinical thrombosis-related research and tailor tissue-type plasminogen activator (tPA) treatment for stroke patients. We quantified the evolution of cerebral thromboemboli using fibrin-targeted glycol chitosan–coated gold nanoparticles and microcomputed tomography, with/without tPA therapy. Methods— We injected thrombi into the distal internal carotid artery in mice (n=50). Fifty-five minutes later, we injected fibrin-targeted glycol chitosan–coated gold nanoparticles, and 5 minutes after that, we treated animals with tPA or not (25 mg/kg). We acquired serial microcomputed tomography images for 24 hours posttreatment. Results— Thrombus burden at baseline was 784×10 3 ±59×10 3 μm 2 for the tPA group (n=42) and 655×10 3 ±103×10 3 μm 2 for the saline group (n=8; P =0.37). Thrombus shrinkage began at 0.5 to 1 hour after tPA therapy, with a maximum initial rate of change at 4603±957 μm 2 /min. The rate of change lowered to ≈61% level of the initial in hours 1 to 2, followed by ≈29% and ≈1% in hours 2 to 3 and 3 to 24, respectively. Thus, 85% of total thrombolysis over 24 hours (≈500 μm 2 , equivalent to 64% of the baseline thrombus burden) occurred within the first 3 hours of treatment. Thrombus burden at 24 hours could be predicted at around 1.5 to 2 hours. Saline treatment was not associated with significant changes in the thrombus burden. Infarct size was smaller in the tPA group versus saline group (18.1±2.3 versus 45.8±3.3 mm 2 ; P r =0.71; P Conclusions— Thromboembolic burden and the efficacy of tPA therapy can be assessed serially, noninvasively, and quantitatively using high-resolution microcomputed tomography and a fibrin-binding nanoparticle imaging agent.

Exosomes and extracellular nanovesicles (NV) derived from mesenchymal stem cells (MSC) may be used for the treatment of ischemic stroke owing to their multifaceted therapeutic benefits that include the induction of angiogenesis, anti-apoptosis, and anti-inflammation. However, the most serious drawback of using exosomes and NV for ischemic stroke is the poor targeting on the ischemic lesion of brain after systemic administration, thereby yielding a poor therapeutic outcome. In this study, we show that magnetic NV (MNV) derived from iron oxide nanoparticles (IONP)-harboring MSC can drastically improve the ischemic-lesion targeting and the therapeutic outcome. Because IONP stimulated expressions of therapeutic growth factors in the MSC, MNV contained greater amounts of those therapeutic molecules compared to NV derived from naive MSC. Following the systemic injection of MNV into transient middle-cerebral-artery-occlusion (MCAO)-induced rats, the magnetic navigation increased the MNV localization to the ischemic lesion by 5.1 times. The MNV injection and subsequent magnetic navigation promoted the anti-inflammatory response, angiogenesis, and anti-apoptosis in the ischemic brain lesion, thereby yielding a considerably decreased infarction volume and improved motor function. Overall, the proposed MNV approach may overcome the major drawback of the conventional MSC-exosome therapy or NV therapy for the treatment of ischemic stroke.

The effective chemotherapeutic drug, doxorubicin (DOX), elicits immunogenic cell death (ICD) and additional anticancer immune responses during chemotherapy. However, it also induces severe side effects and systemic immunosuppression, hampering its wide clinical application. Herein, we constructed cancer-activated DOX prodrug by conjugating the cathepsin B-cleavable peptide (Phe-Arg-Arg-Gly, FRRG) to a doxorubicin (DOX), resulting in FRRG-DOX that self-assembled into cancer-activated DOX prodrug nanoparticles (CAP-NPs). The resulting CAP-NPs were further stabilized with the FDA-approved compound, Pluronic F68. CAP-NPs formed stable prodrug nanoparticles and they were specifically cleaved to cytotoxic DOX molecules only in cathepsin B-overexpressing cancer cells, inducing a cancer cell-specific cytotoxicity. In particular, the CAP-NPs induced ICD through cathepsin B-cleavage mechanism only in targeted cancer cells in vitro. In colon tumor-bearing mice, selectively accumulated CAP-NPs at tumors enhanced antitumor immunity without DOX-related severe toxicity, inflammatory response and systemic immunosuppression. Moreover, cytotoxicity against immune cells infiltrated into tumor microenvironment was significantly reduced compared to free DOX, leading to increased response to checkpoint inhibitor immunotherapy. The combinatorial treatment of CAP-NPs with anti-PD-L1 exhibited high rate of complete tumor regression (50%) compared to free DOX with anti-PD-L1. Concurrently, DOX-related side effects were greatly reduced during chemoimmunotherapy. Collectively, our results suggest that cancer-activated DOX prodrug nanoparticles provide a promising approach to increase clinical benefit by inducing an immune response preferentially only to targeted cancer cells, not to normal cells and immune cells, and potentiates checkpoint inhibitor immunotherapy.

Nanoparticles have resulted in great progress in biomedical imaging and targeted drug delivery in cancer theranostics. To develop nanoparticles as an effective carrier system for therapeutics, chemical structures and physicochemical properties of nanoparticle may provide a reliable means to predict the in vitro characteristics of nanoparticles. However, in vivo fates of nanoparticles, such as pharmacokinetics and tumor targeting efficiency of nanoparticles, have been difficult to predict beforehand. To predict the in vivo fates of nanoparticles in tumor-bearing mice, differences in physicochemical properties and in vitro cancer cell/macrophage uptake of 5 different nanoparticles with mean diameter of 200-250nm were comparatively analyzed, along with their circulation in adult zebrafish. The nanoparticles which showed favorable cellular uptake by macrophages indicated high unintended liver accumulation in vivo, which is attributed to the clearance by the reticuloendothelial system (RES). In addition, blood circulation of nanoparticles was closely correlated in adult zebrafish and in mice that the zebrafish experiment may elucidate the in vivo behavior of nanoparticles in advance of the in vivo experiment using mammal animal models. This comparative study on various nanoparticles was conducted to provide the basic information on predicting the in vivo fates of nanoparticles prior to the in vivo experiments.

Recently, metabolic glycoengineering with bioorthogonal click reactions has focused on improving the tumor targeting efficiency of nanoparticles as delivery vehicles for anticancer drugs or imaging agents. It is the key technique for developing tumor-specific metabolic precursors that can generate unnatural glycans on the tumor-cell surface. A cathepsin B-specific cleavable substrate (KGRR) conjugated with triacetylated N-azidoacetyl-d-mannosamine (RR-S-Ac3 ManNAz) was developed to enable tumor cells to generate unnatural glycans that contain azide groups. The generation of azide groups on the tumor cell surface was exogenously and specifically controlled by the amount of RR-S-Ac3 ManNAz that was fed to target tumor cells. Moreover, unnatural glycans on the tumor cell surface were conjugated with near infrared fluorescence (NIRF) dye-labeled molecules by a bioorthogonal click reaction in cell cultures and in tumor-bearing mice. Therefore, our RR-S-Ac3 ManNAz is promising for research in tumor-specific imaging or drug delivery.

Cancer immunotherapies, including adoptive T cell transfer and immune checkpoint blockades, have recently shown considerable success in cancer treatment. Nevertheless, transferred T cells often become exhausted because of the immunosuppressive tumor microenvironment. Immune checkpoint blockades, in contrast, can reinvigorate the exhausted T cells; however, the therapeutic efficacy is modest in 70-80% of patients. To address some of the challenges faced by the current cancer treatments, here T-cell-membrane-coated nanoparticles (TCMNPs) are developed for cancer immunotherapy. Similar to cytotoxic T cells, TCMNPs can be targeted at tumors via T-cell-membrane-originated proteins and kill cancer cells by releasing anticancer molecules and inducing Fas-ligand-mediated apoptosis. Unlike cytotoxic T cells, TCMNPs are resistant to immunosuppressive molecules (e.g., transforming growth factor-β1 (TGF-β1)) and programmed death-ligand 1 (PD-L1) of cancer cells by scavenging TGF-β1 and PD-L1. Indeed, TCMNPs exhibit higher therapeutic efficacy than an immune checkpoint blockade in melanoma treatment. Furthermore, the anti-tumoral actions of TCMNPs are also demonstrated in the treatment of lung cancer in an antigen-nonspecific manner. Taken together, TCMNPs have a potential to improve the current cancer immunotherapy.

Designer nanoparticles with controlled shapes and sizes are increasingly popular vehicles for therapeutic delivery due to their enhanced cell-delivery performance. However, our ability to fashion nanoparticles has offered only limited control over these parameters. Structural DNA nanotechnology has an unparalleled ability to self-assemble three-dimensional nanostructures with near-atomic resolution features, and thus, it offers an attractive platform for the systematic exploration of the parameter space relevant to nanoparticle uptake by living cells. In this study, we examined the cell uptake of a panel of 11 distinct DNA-origami shapes, with the largest dimension ranging from 50-400 nm, in 3 different cell lines. We found that larger particles with a greater compactness were preferentially internalized compared with elongated, high-aspect-ratio particles. Uptake kinetics were also found to be more cell-type-dependent than shape-dependent, with specialized endocytosing dendritic cells failing to saturate over 12 h of study. The knowledge gained in the current study furthers our understanding of how particle shape affects cellular uptake and heralds the development of DNA nanotechnologies toward the improvement of current state-of-the-art cell-delivery vehicles.

Cathepsin B (CB)-specific molecular imaging probe is applied to monitor the changes of CB expression in 3D cultured chondrocytes during the chondrogenesis. The probe is synthesized with a CB-cleavable peptide linked to a near infrared fluorescence (NIRF) dye and a dark quencher, which can recover the NIRF signal in the presence of CB enzyme. The CB activities in two different sets of chondrocytes are comparatively analyzed. The chondrocytes with higher CB activity show more extensive area of chondrogenesis that CB molecular imaging directly reflects the chondrogenic potency of the cells. The CB probe is expected to provide a reliable prediction for the quality of engineered cartilage by visualizing the activity of the relevant enzyme in chondrocytes.

A suitable liquid chromatography tandem mass spectrometry (LC-MS/MS) method is required to determine pelubiprofen and its active metabolite, trans-alcohol (M-D), in human plasma for pharmacokinetic studies of pelubiprofen preparations. After one-step liquid-liquid extraction (LLE) using methyl tert-butyl ether (MTBE), pelubiprofen, M-D, and tolbutamide (the internal standard, IS) were eluted from a Capcellpak C18 ACR column using a gradient mobile phase consisting of 0.1% formic acid in water and acetonitrile at a flow rate 0.35mL/min. The achieved lower limits of quantitation (LLOQ) of pelubiprofen and M-D were both 15ng/mL (S/N>10) and the standard calibration curves for pelubiprofen and M-D were linear (correlation coefficients >0.99) over the studied concentration range (15-2000ng/mL). Intra- and inter-day precisions were within 7.62% for all analytes and the deviation of assay accuracies was within ±13.23%. The developed method was successfully applied to a pharmacokinetic study of pelubiprofen in healthy Korean male volunteers.

A sensitive and specific method based on liquid chromatographic–tandem mass spectrometric method (LC–MS/MS) has been developed and validated to determine plasma concentrations of olopatadine. Olopatadine and internal standard (IS, loratadine) from human plasma were extracted using solid-phase extraction. Chromatographic separation was achieved on a reversed-phase Capcellpak CR column using the isocratic mobile phase consisted of 70 % acetonitrile and 30 % water containing 10 mM ammonium acetate (adjusted to pH 4.0 with acetic acid). Acquisition was performed in multiple reaction monitoring mode by monitoring the transitions: m/z 337.92 → 164.80 for olopatadine and m/z 383.17 → 336.90 for IS. This method was fully validated. The calibration curve was linear over the concentration range from 0.2 to 100 ng/mL, and correlation coefficients (r2) were greater than 0.99. The low limit of quantitation with a relative standard deviation below 20 % was 0.2 ng/mL. The intraday and interday precisions ranged 6.31–16.80 % and intraday and interday accuracies ranged 91.17–110.08 %. The devised method was successfully applied in a bioequivalence study of two formulations of olopatadine, Allotadine tablet and Allelock tablet in 26 healthy Korean volunteers following single oral administration.

Considering the problems of small interfering RNA (siRNA) delivery using traditional viral and nonviral vehicles, a new siRNA delivery system to enhance efficiency and safety needs to be developed. Here human ferritin-based proteinticles are genetically engineered to simultaneously display various functional peptides on the surface of proteinticles: cationic peptide to capture siRNA, tumor cell targeting and penetrating peptides, and enzymatically cleaved peptide to release siRNA inside tumor cell. In the in vitro treatment of poly-siRNA-proteinticle complex, both of the tumor cell targeting and penetrating peptides are important for efficient delivery of siRNA, and the red fluorescent protein (RFP) expression in RFP-expressing tumor cells is notably suppressed by the delivered siRNA with the complementary sequence to RFP mRNA. It seems that the human ferritin-based proteinticle is an efficient, stable, and safe tool for siRNA delivery, having a great potential for application to in vivo cancer treatment. The unique feature of proteinticles is that multiple and functional peptides can be simultaneously and evenly placed and also easily switched on the proteinticle surface through a simple genetic modification, which is likely to make proteinticles appropriate for targeted delivery of siRNA to a wide range of cancer cells.

The concept of personalized medicine has recently emerged as a promising way to address unmet medical needs. Due to the limitations of standard diagnostic and therapeutic strategies, the disease treatment is moving towards tailored treatment for individual patients, considering the inter-individual variability in therapeutic response. Theranostics, which involves the combination of therapy and diagnostic imaging into a single system, may fulfill the promise of personalized medicine. By integrating molecular imaging functionalities into therapy, theranostic approach could be advantageous in therapy selection, treatment planning, objective response monitoring and follow-up therapy planning based on the specific molecular characteristics of a disease. Although the field of therapy and imaging of its response have been independently developed thus far, developing imaging strategies can be fully exploited to revolutionize the theranostic systems in combination with the therapy modality. In this review, we describe the recent advances in molecular imaging technologies that have been specifically developed to evaluate the therapeutic efficacy for theranostic purposes.

Imaging techniques including computed tomography, magnetic resonance imaging, and positron emission tomography (PET) offer many potential benefits to diagnosis and treatment of cancers. Each method has its own strong and weak points. Therefore, multimodal imaging techniques have been highlighted as an alternative method for overcoming the limitations of each respective imaging method. In this study, we fabricated PET/optical activatable imaging probe based on glycol chitosan nanoparticles (CNPs) for multimodal imaging. To prepare the dual PET/optical probes based on CNPs, both (64)Cu radiolabeled DOTA complex and activatable matrix metalloproteinase (MMP)-sensitive peptide were chemically conjugated onto azide-functionalized CNPs via bio-orthogonal click chemistry, which was a reaction between azide group and dibenzyl cyclooctyne. The PET/optical activatable imaging probes were visualized by PET and optical imaging system. Biodistribution of probes and activity of MMP were successfully measured in tumor-bearing mice.

Matrix metalloproteinase (MMP)-2 and MMP-9 have been known to play the role of essential mediators in angiogenesis. Non-invasive in vivo imaging approach using imaging probes is a potential method of detecting MMP activity in living animals, wherein imaging probes must include the characteristics of non-toxicity, specific targetability, and reasonable signal intensity. Here, we developed MMP-specific and self-quenched human serum albumin (HSA)-based (MMP-HSA) nanoprobes for non-invasive optical imaging of MMP activity during angiogenesis in the mouse hindlimb ischemia model. MMP-specific fluorogenic peptide probes, which were self-quenched with a near-infrared fluorophore and a quencher, were covalently conjugated to HSA (MMP-HSA nanoprobes). MMP-HSA nanoprobes formed stable nanoparticle structures of approximately 36 nm in diameter. Strongly self-quenched MMP-HSA nanoprobes boosted intense fluorescence signals in the presence of MMP-2 and MMP-9. Furthermore, MMP-HSA nanoprobes showed no cytotoxicity in cell culture. Importantly, intravenous injection of MMP-HSA nanoprobes provided longer blood half-life and successful non-invasive optical imaging of MMP activity during angiogenesis in the mouse hindlimb ischemia model. In addition, the MMP activity visualized by MMP-HSA nanoprobes was consistent with the results of zymography, Western blot, and immunohistochemistry. MMP-HSA nanoprobes may be useful for monitoring of the initial process of angiogenesis through non-invasive MMP imaging.

Purpose Pelubiprofen is a novel nonsteroidal anti-inflammatory, analgesic, and antipyretic drug with at least similar efficacy and better tolerability compared with other nonsteroidal anti-inflammatory, analgesic, and antipyretic drugs such as naproxen and aceclofenac. Eperisone hydrochloride is a centrally acting muscle relaxant that performs by blocking calcium channels. The combined use of pelubiprofen and eperisone hydrochloride is increasingly anticipated to promote the clinical effectiveness of pelubiprofen in relieving musculoskeletal symptoms of osteoarthritis, rheumatoid arthritis, and low back pain. No published data are yet available, however, regarding the pharmacokinetic interactions between these 2 drugs when administered concurrently. The objective of this study was to evaluate any pharmacokinetic interactions between pelubiprofen and eperisone hydrochloride in healthy Korean male volunteers. Methods This was a randomized, open-label, crossover study. Each participant was randomly assigned to 1 of 6 treatment sequences and orally received either 45-mg sustained-release pelubiprofen, 75-mg sustained-release eperisone hydrochloride, or both as a single dose in each treatment period, with a 7-day washout period between each treatment. Serial blood samples were collected over 24 hours after dosing, and plasma concentrations of each drug and the major active metabolite of pelubiprofen (trans-alcohol pelubiprofen) were determined by using a validated HPLC-MS/MS system. Pharmacokinetic analyses were conducted by using noncompartmental methods. Findings A total of 24 men (mean ± standard deviation of: age, 29 ± 4 years; weight, 72.5 ± 7.8 kg; body mass index, 23.4 ± 1.9 kg/m 2 ) were enrolled, and 23 participants completed the study. For pelubiprofen, the geometric mean ratios (90% CIs) of C max and AUC 0–∞ were 1.02 (0.87–1.19) and 0.97 (0.88–1.07), respectively. For the major active metabolite of pelubiprofen (trans-alcohol pelubiprofen), the geometric mean ratios (90% CIs) of C max and AUC 0–∞ were 1.05 (0.98–1.13) and 1.04 (1.01–1.07). For eperisone, the geometric mean ratios (90% CIs) of C max and AUC 0–∞ were 0.87 (0.67–1.15) and 1.05 (0.85–1.30). None of the study participants experienced serious adverse events during the study. Implications No clinically significant changes were noted in the pharmacokinetic interactions of pelubiprofen, the major active metabolite of pelubiprofen (trans-alcohol pelubiprofen), and eperisone hydrochloride between monotherapy and combination therapy with 45-mg sustained-release pelubiprofen and 75-mg sustained-release eperisone hydrochloride.

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of stroke than relying on indirect measurements, and will be a potent and robust vascular research tool. We use an optical imaging approach that labels thrombi with a molecular imaging thrombus marker — a Cy5.5 near-infrared fluorescent (NIRF) probe that is covalently linked to the fibrin strands of the thrombus by the fibrin-crosslinking enzymatic action of activated coagulation factor XIIIa during the process of clot maturation. A micro-computed tomography (microCT)-based approach uses thrombus-seeking gold nanoparticles (AuNPs) functionalized to target the major component of the clot: fibrin. This paper describes a detailed protocol for the combined in vivo microCT and ex vivo NIRF imaging of thromboemboli in a mouse model of embolic stroke. We show that in vivo microCT and fibrin-targeted glycol-chitosan AuNPs (fib-GC-AuNPs) can be used for visualizing both in situ thrombi and cerebral embolic thrombi. We also describe the use of in vivo microCT-based direct thrombus imaging to serially monitor the therapeutic effects of tissue plasminogen activator-mediated thrombolysis. After the last imaging session, we demonstrate by ex vivo NIRF imaging the extent and the distribution of residual thromboemboli in the brain. Finally, we describe quantitative image analyses of microCT and NIRF imaging data. The combined technique of direct thrombus imaging allows two independent methods of thrombus visualization to be compared: the area of thrombus-related fluorescent signal on ex vivo NIRF imaging vs. the volume of hyperdense microCT thrombi in vivo.

Establishment of an appropriate cell labeling and tracking method is essential for the development of cell-based therapeutic strategies. Here, we are introducing a new method for cell labeling and tracking by combining metabolic gylcoengineering and bioorthogonal copper-free Click chemistry. First, chondrocytes were treated with tetraacetylated N-azidoacetyl-D-mannosamine (Ac4ManNAz) to generate unnatural azide groups (-N3) on the surface of the cells. Subsequently, the unnatural azide groups on the cell surface were specifically conjugated with near-infrared fluorescent (NIRF) dye-tagged dibenzyl cyclooctyne (DBCO-650) through bioorthogonal copper-free Click chemistry. Importantly, DBCO-650-labeled chondrocytes presented strong NIRF signals with relatively low cytotoxicity and the amounts of azide groups and DBCO-650 could be easily controlled by feeding different amounts of Ac4ManNAz and DBCO-650 to the cell culture system. For the in vivo cell tracking, DBCO-650-labeled chondrocytes (1 × 10(6) cells) seeded on the 3D scaffold were subcutaneously implanted into mice and the transplanted DBCO-650-labeled chondrocytes could be effectively tracked in the prolonged time period of 4 weeks using NIRF imaging technology. Furthermore, this new cell labeling and tracking technology had minimal effect on cartilage formation in vivo.

Theragnostic nanoparticles (NPs) contain diagnostic and therapeutic functions in one integrated system, enabling diagnosis, therapy, and monitoring of therapeutic response at the same time. For diagnostic function, theragnostic NPs require the inclusion of noninvasive imaging modalities. Among them, optical imaging has various advantages including sensitivity, real-time and convenient use, and non-ionization safety, which make it the leading technique for theragnostic NPs. For therapeutic function, theragnostic NPs have been applied to chemotherapy, photodynamic therapy, siRNA therapy and photothermal therapy. In this review, we present a recent progress reported in the development and applications of theragnostic NPs for cancer therapy. More specifically, we will focus on theragnostic NPs related with optical imaging, highlighting promising strategies based on optical imaging techniques.

A rapid, simple and fully validated LC-MS/MS method was developed and validated for the determination of megestrol acetate in human plasma using tolbutamide as an internal standard (IS) after one-step liquid–liquid extraction with methyl-tert-butyl-ether. Detection was performed using electrospray ionization in positive ion multiple reaction monitoring mode by monitoring the transitions m/z 385.5 267.1 for megestrol acetate and m/z 271.4 155.1 for IS. Chromatographic separation was performed on a YMC Hydrosphere C18 column with an isocratic mobile phase, which consisted of 10 mm ammonium formate buffer (adjusted to pH 5.0 with formic acid)–methanol (60:40, v/v) at a flow rate of 0.4 mL/min. The achieved lower limit of quantitation (LLOQ) was 1 ng/mL (signal-to-noise ratio > 10) and the standard calibration curve for megestrol acetate was linear (r > 0.99) over the studied concentration range (1–2000 ng/mL). The proposed method was fully validated by determining its specificity, linearity, LLOQ, intra- and inter-day precision and accuracy, recovery, matrix effect and stability. The validated LC-MS/MS method was successfully applied for the evaluation of pharmacokinetic parameters of megestrol acetate after oral administration of a single dose 800 mg of megestrol acetate (Megace™) to five healthy Korean male volunteers under fed conditions. Copyright © 2012 John Wiley & Sons, Ltd.

To optimize tumor targetability of nanosized liposomes for application as drug carriers, various liposomes are prepared by incorporating different amounts (10, 30, and 50 wt%) of cationic, anionic, and PEGylated lipids into neutral lipid. In vivo near-infrared fluorescence images reveal that PEG-PE/PC liposomes display high tumor accumulation in tumor-bearing mice, while large amounts of DOTAP/PC liposomes are rapidly captured in the liver, resulting in poor tumor accumulation. These results demonstrate that optimization of the surface properties of liposomes is very important for their tumor targetability, and that in vivo imaging techniques are useful in developing and optimizing nanosized liposome-based drug carriers.

Cathepsin B and matrix metalloproteinase (MMP) play key roles in tumor progression by controlled degradation of extracellular matrix. Consequently, these proteases have been attracted in cancer research, and many imaging probes utilizing these proteases have been developed. Our groups developed cathepsin B and MMP imaging nanoprobes based on polymer nanoparticle platform. Both cathepsin B and MMP imaging probes used near-infrared fluorescence (NIRF) dye and dark-quencher to for high sensitivity, and protease-sensitive peptide sequence in each probe authorized high specificity of the probes. We compared the bioactivities of cathepsin B and MMP sensitive probes in cancer-related environments to investigate the biological property of the probes. As a result, cathepsin B probe showed fluorescence recovery after the probe entered the cytoplasm. This property could be useful to evaluate the cytoplasmic targeted delivery by using probe-conjugated nanoparticles in vivo. On the other hand, MMP probe was superior in specificity in vivo and tissue study. This comparative study will provide precise information about peptide-based optical probes, and allow their proper application to cancer diagnosis.

Cathepsin B and matrix metalloproteinase (MMP) play key roles in tumor progression by controlled degradation of extracellular matrix. Consequently, these proteases have been attracted in cancer research, and many imaging probes utilizing these proteases have been developed. Our groups developed cathepsin B and MMP imaging nanoprobes based on polymer nanoparticle platform. Both cathepsin B and MMP imaging probes used near-infrared fluorescence (NIRF) dye and dark-quencher to for high sensitivity, and protease-sensitive peptide sequence in each probe authorized high specificity of the probes. We compared the bioactivities of cathepsin B and MMP sensitive probes in cancer-related environments to investigate the biological property of the probes. As a result, cathepsin B probe showed fluorescence recovery after the probe entered the cytoplasm. This property could be useful to evaluate the cytoplasmic targeted delivery by using probe-conjugated nanoparticles in vivo. On the other hand, MMP probe was superior in specificity in vivo and tissue study. This comparative study will provide precise information about peptide-based optical probes, and allow their proper application to cancer diagnosis.

Nanomedicine is the biomedical application of nanoscale materials for diagnosis and therapy of disease. Recent advances in nanotechnology and biotechnology have contributed to the development of multifunctional nanoparticles as representative nanomedicine. They were initially developed to enable the target-specific delivery of imaging or therapeutic agents for biomedical applications. Due to their unique features including multifunctionality, large surface area, structural diversity, and long circulation time in blood compared to small molecules, nanoparticles have emerged as attractive preferences for optimized therapy through personalized medicine. Multimodal imaging and theragnosis are the cutting-edge technologies where the advantages of nanoparticles are maximized. Because each imaging modality has its pros and cons, the integration of several imaging agents with different properties into multifunctional nanoparticles allows precise and fast diagnosis of disease through synergetic multimodal imaging. Moreover, nanoparticles are not only used for molecular imaging but also applied to deliver therapeutic agents to the disease site in order to accomplish the simultaneous imaging and therapy called theragnosis. This tutorial review will highlight the recent advances in the development of multifunctional nanoparticles and their biomedical applications to multimodal imaging and theragnosis as nanomedicine.

Background and Purpose— High experimental variability in mouse embolic stroke models could mask the effects of experimental treatments. We hypothesized that imaging thrombus directly would allow this variability to be controlled. Methods— We optically labeled thrombi with a near-infrared fluorescent (NIRF) probe C15 that is covalently linked to fibrin by factor-XIIIa. Labeled thrombus was injected into the left distal internal carotid artery (ICA) of C57/BL6 mice (n=47), near its bifurcation, and laser-Doppler cerebral-blood-flow (CBF) was assessed for 30 minutes. NIRF thrombus imaging was done ex vivo at 24 hours. Results— CBF variably decreased to 43.9±17.3% at 5 minutes (rCBF; 11.2∼80.4%). NIRF thrombus imaging at 24 hours showed variability in distribution (ICA bifurcation, adjacent and/or remote areas) and burden (2279±1270 pixels; 0∼5940 pixels). Final infarct size was also variable (21.0±10.3%; 4.7∼60.3% of the bihemispheric volume). Despite this heterogeneity, a strong thrombus-infarct correlation was maintained. The left hemispheric target infarct size (% of the hemisphere) correlated with thrombus burden, as a stronger predictor of infarct volume ( P P =0.02, r=−0.34). The infarct size was best predicted by a combination of thrombus imaging and CBF: left-hemispheric big-thrombi (>1865 pixels)/low-rCBF (≤42%) had an infarct volume of 56.9±10.4% (n=12), big-thrombi/high-rCBF had 45.9±23.5% (n=11), small-thrombi/low-rCBF 35.7±17.3% (n=11) and small-thrombi/ high-rCBF 27.3±16.4% (n=12). Conclusions— This is the first study to demonstrate that the highly heterogeneous nature of the mouse embolic stroke model can be characterized and managed by using near-infrared fluorescent thrombus imaging combined with CBF monitoring to stratify animals into useful subgroups.

Summary Recent progress in bio and nanotechnology enables the development of various nanoprobes for biomedical imaging. The detection and imaging of specific changes in biological microenvironments play key roles in many fields such as biological mechanism study, drug screening, diagnosis of many diseases, and monitoring of therapeutic responses. Especially to obtain fine images in living systems, there are many requirements such as stability in complex condition, efficient accumulation in target site, and high sensitivity to the target molecule. For this purpose, many researchers have developed a number of nano-size probes sensitive to the external changes which are valuable from biomedical point of view. Herein, we will review the on-going challenges of developing novel nanoprobes to detect chemical or biological changes such as enzyme, oxygen, and pH, and applying them to biomedical imaging in living systems.

We report a new apoptosis nanoprobe (Apo-NP) designed on the basis of a polymer nanoparticle platform. This simple one-step technique is capable of boosting fluorescence signals upon apoptosis in living cells, enabling real-time imaging of apoptosis in single cells and in vivo. The Apo-NP efficiently delivers chemically labeled, dual-quenched caspase-3-sensitive fluorogenic peptides into cells, allowing caspase-3-dependent strong fluorescence amplification to be imaged in apoptotic cells in real-time and at high resolution. The design platform of the Apo-NP is flexible and can be fine-tuned for a wide array of applications such as identification of caspase-related apoptosis in pathologies and for monitoring therapeutic efficacy of apoptotic drugs in cancer treatment.

Herein, we developed matrix metalloprotease (MMP) sensitive gold nanorods (MMP-AuNR) for cancer imaging and therapy. It was feasible to absorb NIR laser and convert into heat as well as visualize MMP activity. We showed the possibility of gold nanorods as a hyperthermal therapeutic agent and MMP sensitive imaging agent both in vitro and in vivo condition. The results suggested potential application of MMP-AuNR for simultaneous cancer diagnosis and therapy.

Matrix metalloproteinases (MMPs) have been shown to be abundant in pathological conditions such as cancer, osteoarthritis (OA), and rheumatoid arthritis (RA). The extent of MMPs detected in biological samples provides important clinical information for diagnosis, prognosis, and therapeutic monitoring of various diseases relating with MMPs. Herein, we developed a new high-throughput MMP diagnostic kit (MMP-D-KIT) based on a 96-well plate by immobilizing MMP-13 specific fluorogenic peptide probes (MMP peptide probe), which is a pair consisting of a near-infrared (NIR) fluorophore (Cy5.5) and a quencher (BHQ-3), onto the biocompatible glycol chitosan (GC) polymer anchored 96-well plate. When MMP enzymes were simply added and incubated in a MMP-D-KIT, the fluorescence of each well was recovered and the fluorescence intensity showed distinct difference within minutes through NIR fluorescence imaging system. The fluorescence was recovered not only by MMP-13 activity, but also by other MMPs activity. Furthermore, recovery of NIR fluorescent signals in MMP-D-KIT was proportional to concentrations of immobilized MMP peptide probe-GC conjugates and, importantly, MMP concentration. The MMP-D-KIT is most specific for target MMP, compared with other enzymes including caspase-3 and 20s proteasome. Additionally, the MMP-D-KIT was used to detect MMP activity in biological samples such as synovial fluid from 12 OA patients (grades 1-4 based on the Kellgren-Lawrence grading scale). It was found that the fluorescence intensity measured using MMP-D-KIT decidedly correlates with the progression of OA. The MMP-D-KIT could be applicable in detecting MMP activities in various biological samples and evaluating the effects of MMP inhibitors in a rapid and easy fashion.

The purpose of the present study was to evaluate the bioequivalence of meloxicam capsule, capsule( Boehringer Ingelheim Ltd., Korea) as a reference drug and capsule (Kukje Pharma Ind. Co., Ltd., Korea) as a test drug, according to the guidelines of Korea Food and Drug Administration(KFDA). Thirty two healthy male Korean volunteers received capsule containing meloxicam 7.5 mg in a crossover study. There was a one-week above washout period between the doses. Plasma concentrations of meloxicam were monitored for over a period of 72 hr after administration by using a high performance liquid chromatography-tandem mass spectrometer(LC-MS/MS). (the area under the plasma concentration-time curve from time zero to 72 hr), (maximum plasma drug concentration) and (time to reach ) were complied from the plasma concentration-time data. Analysis of variance(ANOVA) test was utilized for the statistical analysis of the parameters using logarithmically transformed and . The 90% confidence intervals of the ratio and the ratio for were log 0.8605-log 0.9847 and log 0.9765-log 1.1503, respectively. These values were within the acceptable bioequivalence intervals of log 0.80-log 1.25, recommended by KFDA. In all of these results, we concluded that capsule was bioequivalent to capsule, based on the rate and extent of absorption.

A rapid and simple procedure was developed for the determination of cephradine in human plasma using liquid chromatography coupled with electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). After trichloroacetic acid (TCA) precipitation of proteins from plasma samples, cephradine and cefaclor (the internal standard; IS) were eluted on a CN column. The isocratic mobile phase used consisted of acetonitrile-water-formic acid (25:75:0.1, v/v/v). Cephradine and the IS were both detected in multiple reaction monitoring (MRM) mode at the transitions: m/z 350.0 --> 90.8 for cephradine and m/z 368.1 --> 106.0 for the IS, respectively. The calibration curve was linear over the concentration range from 0.05 to 50 microg/ml, and correlation coefficients were greater than 0.996. The coefficient of variation of assay precision was less than 9.36%, and its accuracy ranged from 87.92% to 111.16%. The chromatographic run time for each plasma sample was less than 3 min. The developed method was successfully applied to a bioequivalence study of cephradine in healthy male volunteers.

The purpose of this study was to evaluate the bioequivalence of two nateglinide tablets, tablet (ILDONG Pharm. Co., Ltd., Seoul, Korea, reference drug) and tablet (ILHWA. Co., Ltd., Seoul, Korea, test drug), according to the guidelines of Korea Food and Drug Administration (KFDA). Thirty-five healthy male volunteers, years in age and in body weight, were divided into two groups and a randomized cross-over study was employed. After a tablet containing 90 mg of nateglinide was orally administrated, blood was taken at predetermined time intervals over a period of 8 hr and concentrations of nateglinide in plasma were monitored using LC-MS/MS. Pharmacokinetic parameters such as AUCt (the area under the plasma concentration-time curve from time 0 to 8 hr), (maximum plasma drug concentration) and (time to reach ) were calculated and analysis of variance (ANOVA) test was utilized for the statistical analysis of the parameters using logarithmically transformed and and untransformed . The 90% confidence intervals of the ratio and the ratio for were and , respectively. Since these values were within the acceptable bioequivalence intervals of , recommended by KFDA, it was concluded that tablet was bioequivalent to tablet, in terms of both rate and extent of absorption.

The purpose of the present study was to evaluate the bioequivalence of two pioglitazone HCl tablets, , tablets (Lilly Korea. Ltd., Korea) as a reference drug and , tablets (Reyon Pharm. Co., Ltd., Korea) as test drug, according to the guideline of Korea Food and Drug Administration (KFDA). Twenty-four healthy male Korean volunteers received one tablet containing pioglitazone HCl 15 mg in a crossover study. There was a one-week washout period between the doses. Plasma concentrations of pioglitazone were monitored for over a period of 36 hr after administration by using a high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The area under the plasma concentration-time curve from time zero to 36 hr (), maximum plasma drug concentration () and time to reach () were complied from the plasma concentration-time data. Analysis of variance (ANOVA) test was utilized for the statistical analysis of the parameters using logarithmically transformed and . The 90% confidence intervals of the ratio and the ratio for /. were log 0.8753-log 1.1286 and log 0.8669-log 1.1734, respectively. These values were within the acceptable bioequivalence intervals of log 0.80-log 1.25, recommended by KFDA. In all of these results, we concluded that the . tablet was bioequivalent to the . tablet, based on the rate and extent of absorption.